In this field there has been a need for an up-drill pressing system which is economical, and durable and practical enough for mass sales for making mass production low prices possible. Part of the practicality must come from adaptation to a hand drill the buyer probably already has. But the remainder of the practicality must come from good operating characteristics and economy of construction.
Some patents have shown ways to drill away from a base: For example upwardly. Among these are Palik, U.S. Pat. No. 2,720,125 (1955), Baublitz, U.S. Pat. No. 2,879,677 (1959), Agoston, U.S. Pat. No. 4,442,905 (1984) and Yang, U.S. Pat. No. 4,810,137 (1989).
Of these, the Yang patent has no power-leverage system, using hand pressing on the drill housing itself with a brace limiting drilling depth.
The Baublitz patent has no drill carriage moving only up and down on a post, and a separate post-drill-carriage moving not up and down and sideways with respect to a post simultaneously, as would seem to cause the drill bit to move in an arc rather than straight.
The Palik patent has a feature making it unsuitable for use in up-drilling under cars. Its drill is directly on top of its post, good for many uses, but causing the height to be such that, at minimum height, it would seem too tall for the usual drilling upward under a car by a mechanic laying horizontally on one of the common castor wheeled back supports.
Operating economy is also important. Tilt-plates making bind-grip on a post, or shaft, are widely used in furniture clamps. They chew the shaft. Short use-life results, from shaft damage, and loss of grip, from wear on tilt-plates and shaft, makes inoperability in continued use. The post-gripping pawl, dog or tilt-plate of the Palik patent is, therefore, a disadvantage in continued use, economy being important to professional auto-mechanics.
There is no teaching in the Palik patent of removability of the base-mounted tube-post from the collar that carries the lower leverage-pivot, whereby the concept of replaceability of a base-attached tube-post with a shorter such post for under-car drilling, or a longer such post, for drilling one side wall of a room with the base against another side wall of the room, as in the invention hereof, is not taught. Replacement of an inner telescoping member with a longer or a shorter one is a concept not taught in the Palik patent either, but would appear possible at least for wall-to-wall drilling. But for under-car drilling the putting-in of a very short base-mounted post section is a concept, hereof, needed. Especially is it needed where the drill is on top of the post, but even then, the drill would not seem to be short enough to fit under a car.
A modifying of patented proposed up-drills by use of features from down-drills, could theoretically have been done many decades ago, but has been unobvious and hidden from the drill manufacturers, and the public has gone without these advantages for these many decades.
In the prior art background is the Mar. 31, 1959 U.S. Pat. No. 2,879,677 to Mr. M. H. Baublitz, titled: SUPPORTING OPERATING DEVICE FOR DRILLS AND THE LIKE. The device to U.S. Pat. No. 2,879,677 had the good features of hand-drill mounting, away-from-the-base-drilling, and transverse lever pressing. However, it had disadvantages and has never come into general usage in some main needs.
A major need for drilling away from a base is in drilling upwards under an automobile. A man holding a hand drill in such a position becomes tired very quickly as distinguished from other uses in which it is possible to drill downward or horizontally with a hand drill. The advantage for an auto mechanic would be in drilling away from a base rested on the ground or a work floor under a car with power because of the lever. The lever in U.S. Pat. No. 2,879,677 was designed to be pressed on by a foot, but it could have been put into position for hand operation under a car.
An objective hereof is to provide such a drill system with an easily adjusted total height, to fit under a car when needed and yet to be extendable by the addition of extension pipe sections until the base can even be disposed on the floor of a room while the drilling is being done at the ceiling of the same room.
Another objective is to provide economy by having a drill carriage slidable upon the same post that a lever pivot mounting is on. In U.S. Pat. No. 2,879,677 a drill carriage is not slidable on the base-post but pivots with respect thereto. This has a disadvantage of causing the drill bit to move in an arc rather than directly forward. It is an objective of this invention therefore to provide for the drill bit to move always in exact parallelism with the base-post in a sliding rather than a pivoting manner for a more precision drilling and for a lesser strain on drill bits. Hard steel drill bits are brittle and can break easy if not moved in direct alignment with the bit axis.
Another objective hereof is to provide a base-post formed of threaded pipe sections to be extendable with commonly available threaded pipe. This has a merchandising advantage because it is not necessary for a dealer to stock drilling systems of many sizes since the purchase of a drill base and basic base-post unit are sufficient to supply for many uses since threaded pipe of a desired length is easy to obtain in the popular diameters.
An objective is to provide a base with an attached coupler extending therethrough. The coupler is capable of threadedly receiving a base-post of any length.
Whereas the base-post U.S. Pat. No. 2,879,677 was square, it is an objective hereof to provide a cylindrical threaded base-post which can be extended by attaching another post section by means of a common pipe coupler additional to the coupler which is fixed to the base itself.
Another objective is to provide for attachment of a post extension into that side of the base-attached coupler which is on the opposite side of the base from the drill. This has the advantage of speed as compared with the disconnection of a primary base-post from the base in order to insert a secondary more extension base-post section. This speed is not detracted from by the absence of the base from the farthest end of the extension post section that has been attached to the backside of the base, because it has been discovered that one can just grasp a baseless backside extension as described, against some solid object and no base will be needed since the pressure of the object against the threaded end of such an extension does not cause the threads to become damaged as the pressure is only against the end and further has been discovered that the base itself although it is not resting against any solid surface can be easily used as a lever to be gripped by an operator's hand to prevent rotation of a base-post because of the rotation drilling floor.
Another objective here is to provide an inexpensive adjustable lever fulcruming system, adjustable by the same wing-bolt that serves as the lever pivot bolt as accomplished by a lock nut set against the lever with a desirable positioning so that the lever rotates freely but the lever is held into a pivot-plane without wobbling.
A U.S. Pat. No. 2,405,110 issued Jul. 31, 1945 to J. Bullock and titled: DRILL. It had the feature of adjustable length for a drill system that drilled away from a base but its extending was done by screws in the base-post section and not by threaded couplers. A greater versatility is achieved herein by the threaded coupler way because threaded pipe of many lengths is often available and can be purchased already threaded quite inexpensively.
In U.S. Pat. No. 2,405,110 the drill is supported with its bit in alignment with the base-post. This requires a drill holding cradle system adapted to fit one size of drill. It is an objective of this invention to provide a cradle system using divergent drill engaging surface which can engage drills with housings of many diameters and in a manner primarily engaging the drill between the two surfaces, and in which the two surfaces are not themselves each concave, as is the manner in the U.S. Pat. No. 2,879,677.
A chief objective hereof is to provide a drill system capable of use in many, many ways and yet which is inexpensive, and further in which, if a drill should fail and another of a differenct size is all that is available, the other drill can be substituted easily into the drill system hereof.